1. Field of the Invention
The present invention relates to devices for dissipating high voltage electrical arcs which can occur around insulators used to support power transmission lines and in particular to such a device retro-fittable on conventional insulators used in the static line of such high voltage transmission lines.
2. Description of the Prior Art
A typical high voltage transmission line includes a plurality of substantially parallel conductors operating at high voltages such as for example 345 KV, 765 KV and the like. These transmission lines also include one or more static lines grounded at the terminal ends of the transmission line. Insulating of the static line can create a problem when the static line is subjected to a high voltage surge such as may occur when the line is struck by lightning or during significant power load changes, typically caused by transient conditions. These high voltage surges can cause arcing over or around the insulators supporting the static line on the transmission line towers. Such arcing can damage the insulators by causing them to shatter or by depositing a conductive film in the insulator surface, this film being produced by minute metallic particles carried by the electric arc.
One prior art method of eliminating such arcing has been to provide lightning arrestors or similar devices to protect each of the insulators. These devices can be relatively expensive thereby negating genuine cost savings by their installation. It is also difficult to ascertain when such prior art devices have been destroyed, thereby adding significant cost for inspection and testing.
There, therefore, exists a need for a reasonably inexpensive device which will dissipate electrical arcing around insulators when the lines which they are supporting are subjected to high voltage surges and to provide such a device which can be inexpensively retro-fitted to existing "generic" insulators.